Enhanced H₂S Gas Sensing Properties of the Hierarchical CuO Hollow Microspheres

Abstract

Hierarchical CuO hollow microspheres were synthesized through a facile hydrothermal method. The as-prepared samples were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The results show that the hierarchical CuO hollow microspheres with uniform size of 3 μm are self-assembled by hundreds of primary nanorods with diameters of about 20 nm. The wall thickness of the hollow microspheres is about 200 nm. The hierarchical CuO hollow microspheres exhibit good sensing performance in H2S detection. The optimal operating temperature is 180°C, and, in a large range, the hierarchical CuO hollow microspheres display excellent linear sensing performance in ethanol detection. The detecting limit is lower to 1 ppm. Furthermore, the hierarchical CuO hollow microspheres demonstrate excellent selectivity in H2S detection. The sensing mechanism also has been discussed. It can be expected that the novel morphology of the hierarchical CuO hollow microspheres may bring amazing development for H2S detection.